Chatelain etal
tachograph



Sept. 7, 1965 o. CHATELAIN ETAL TACHOGRAPH Filed March 15, 1962 2 Sheets-Sheet l Sept. 7, 1965 o. CHATELAIN ETAL 3,205,502

TACHOGRAPH Filed March 15, 1962 2 Sheets-Sheet 2 United States Patent 3,205,502 TACHOGRAPH Oscar Chatelain and Maurice Jeanmonod, both of La Chaux-de-Fonds, Switzerland, assignors to Zenith S.A., Le Locle, Switzerland, a Swiss company Filed Mar. 15, 1962, Ser. No. 179,993 Claims priority, application Switzerland, Sept. 15, 1961, 10,765/ 61 2 Claims. (Cl. 346-18) Tachographs are already known, which provide a record or graph on rotary discs driven in rotation, in registry with one or more tracing styluses, by a clockwork rigid with the cover of said tachographs.

In a number of the prior instruments, the record discs are secured to the cover by means of an arrangement extending above the clockwork, which is then fitted at the center of the cover.

Such tachographs are comparatively high because the speed-reducing gears are fitted directly between the discsecuring means and the clockwork movement. Furthermore, these tachographs have a drawback in that they must be entirely dismantled whenever the clockwork movement is to be repaired, so that they are unfit for use during a comparatively long down time.

In other, more recent tachographs, the various parts of the clockwork and also the speed-reducing gears are arranged, underneath the speed-indicating dial, in sideby-side relationship in a common plane, so as to reduce to the utmost the height of the tachographs. The latter have however the same drawbacks as those referred to above, consisting in that it is necessary to entirely dismantle them when repairing the clockwork The present invention has for its object a tachograph for vehicles, wherein the measuring mechanisms and at least one tracing member controlled by the latter, are carried inside a casing to which is pivotally secured a cover provided with at least one member indicating the measured speed, together with a milemeter and an arrangement for positioning and carrying along at least one to graph-carrying disc in registry with the tracing members, so as to form curves of the measured magnitudes, and lastly also a clockwork controlling the arrangement.

According to the invention, the movement of the clockwork is removably carried by the cover eccentrically with reference to the disc-carrying means, while means connect kinematically the clockwork movement with the carrying means.

The accompanying drawings illustrate, by way of example, a preferred embodiment of my invention. In said drawings:

FIG. 1 is a plan view of the tachograph in its open position.

FIGS, 2 and 3 are detail views of the cover as seen from the back and from the front respectively.

FIG. 4 is a cross-section view taken through line IV--IV of FIG. 2.

The tachograph illustrated (FIG. 1) includes a casing 1 to which is pivotally secured at 2 a cover 3. Inside the casing are arranged tracing styluses 4, 5 and 6, adapted to record the speed of a vehicle, the duration of the stoppage periods and of the running periods of the vehicle and also the distance travelled. The ends of the styluses project through a slot 7. The styluses are shifted in a conventional manner by means which are not illustrated and which are carried inside the casing 1.

The cover is constituted by an annular rim 8 provided with a glass insert 8a behind which is secured a plate through the agency of uprights or spaces 9 rigid with a dial 11. A first space is defined between the cover and a frontside of plate 10. A second space is defined by the casing 1 and a backside of the plate 10, The dial is 3,205,502 Patented Sept. 7, 1965 provided with two indicating areas, to wit: an outer annular area carrying a scale ranging between 10 and 100 over which a hand 12 indicates visually the velocity of the vehicle and an inner area carrying an annular time scale or indicia including twelve radial lines, in registry with which the hands 13 and 14 move.

At its upper end, the dial is provided with a rectangular gate 15 through which a fraction of the edge of a milemeter appears in view. The milemeter is carried by the plate 10, whereas the lower part of the dial carries a visually indicating signal 16, for example a red lamp, which is illuminated automatically whenever the hand 12 indicates a predetermined limit speed.

The securing of the cover to the casing is performed by means of a lock 17 rigid with the rim 8.

The hands 13 and 14 are time indicating hands driven by a clockwork 18 controlled by a spring mechanism or by an electric motor also carried by the plate 10. The clockwork is eccentrically carried by the plate, The clockwork is secured to the backside of plate 10 by three screws 19 accessible when the cover is open so that it may be readily dismantled and replaced. The tachograph is provided with a winding key 20 and a knob 21 for setting the hands to time.

The hands are connected with a driving spindle 22 of the movement through a speed-reducing gear clearly shown in FIGS. 3 and 4. The hour hand 13 is controlled by the wheels 23 and 24 and the minute hand 14 by the wheels 23, 25 and 26. The wheels 23 and 25 are carried in a loose condition on an intermediate spindle 27 carried by the plate 10, whereas the wheels 24 and 26 are rigid with sleeves 28 and 29 respectively, arranged concentrically with reference to each other and carrying the corresponding hands 13 and 14.

The speed-indicating hand 12 is rigid with one end of a spindle 30 extending through the sleeve 29 and revolvably carried in a support 31 rigid with a square bridge 32 carried by the plate 10 through three spacers 33. The spindle 30 is subjected to the return action of a spiral spring 34 urging the hand 12 against a stop 12a carried by the dial 11.

The support 31 revolvably carries coaxially with the spindle 30 a sleeve 35 rigid at mid-height with a plate 36 and provided with an outer thread 37. The sleeve and its plate 36 are kinematically connected with the pinion 26 through wheels 38 and 39, the wheel 39 meshing with a Wheel 40 rigid with the sleeve 35. The wheels 38, 39 and 40 have a size such than when the hour hand executes one complete revolution over the dial, the plate 36 revolves by 26/24 x 360.

Inside the sleeve is fitted a knob 41 rigid with the end of the spindle 30 and provided with a longitudinal slot 42 engaged by a movable projection 43 when the cover is folded back over the casing, the position of said projection varying with the speed that is being measured.

The plate and the clockwork movement are covered by a dust protector 44 (FIG. 1) formed by a cylindrical dished part, the bottom of which extends flush with the plate 36 and is provided in its central area with a circular opening which is not illustrated and the size of which corresponds with that of the plate. The dust protector is provided with a flap 46, with a selecting tongue 47 and with a stop 48. It is secured to the plate 10 through any suitable means.

The tachograph illustrated and described is intended more particularly for the recording of the magnitude measured and recorded on a stack 49 of graph-carrying discs illustrated diagrammatically by a circle drawn in dot-and-dash lines; but, of course, the instrument may be used with a single disc.

It is apparent that such a stack is constituted for instance, by six or seven records or discs provided each with a radial slot, the breadth of which corresponds to 2/26 of their perimeter, which discs are stacked in a manner such that the ridges defining the different slots form through their succession a helical surface. The discs are fitted on a socket, the height of which is greater than the height of the stack, they are positioned over the cover of the tachograph through engagement of the socket over the sleeve 35 and are held fast against the plate 36 by a tapped nut 50. The discs forming the stack are rigidly secured to the socket, for instance through radial projections engaging corrugations in the socket.

Once every twenty-four hours, a completed disc is urged by the tongue 47 against the stop 48, which stops its movement so that the styluses continue drawing their records on the immediately underlying disc. With such a tachograph, it is consequently possible to continuously record the magnitudes measured during a succession of days What we claim is:

1. In a tachograph, a cup-shaped casing, a cover pivotally mounted on said casing and comprising a rim, a crystal mounted in said rim, a dial mounted in said rim and spaced back of said crystal, a plate spaced back of said dial and fixed relative thereto, a speed-indicating hand between said dial and crystal, a central spindle carrying said hand and extending rearwardly through said dial and plate and into the interior of said casing, driving means in said casing coupling with said spindle to drive it, a time-indicating hand between said dial and crystal, a shaft coaxial with said spindle and carrying said timeindicating hand, a self-contained clockwork unit disposed in said casing on the rear of said plate wholly at one side of said spindle, means removably securing said clockwork nnit to the rear of said plate for easy removal as a complete unit, said clockwork unit having a rotary output member aligned with an opening in said plate, means including gear means between said dial and plate drivingly connecting said shaft of said time-indicating hand with said output member of said clockwork unit to be driven thereby, a chart-holding member rotatably mounted coaxial with said spindle and having a chart-supporting surface in a plane immediately back of said clockwork unit, means including said gear means drivingly connecting said chart-carrying member with said output member of said clockwork unit and said time-indicating hand shaft, and a stylus in said casing in position for engagement with a chart on said chart-holding member, said cover being swingable by said pivotal mounting to an open position affording access to said complete removable clockwork unit.

2. A tachograph according to claim 1, in which said means drivingly connecting said chart-holding member with said clockwork unit and time-indicating hand shaft includes a second shaft offset laterally from said spindle, a gear on said further shaft, and a gear on said chartholding member driven by said last-mentioned gear.

References Cited in the file of this patent UNITED STATES PATENTS 1,373,204 3/21 Phelps 346-137 X 2,982,594 5/61 Riegger et al. 346-l8 FOREIGN PATENTS 624,659 4/27- France. 769,045 2/57 Great Britain. 779,475 7/57 Great Britain.

LEO SMILOW, Primary Examiner. 

1. IN A TECHOGRAPH, A CUP-SHAPED CASING, A COVER PIVOTALLY MOUNTED ON SAID CASING AND COMPRISING A RIM, A CRYSTAL MOUNTED IN SAID RIM, A DIAL MOUNTED IN SAID RIM AND SPACED BACK OF SAID CRYSTAL, A PLATE SPACED BACK OF SAID DIAL AND FIXED RELATIVE THERETO, A SPEED-INDICATING HAND BETWEEN SAID DIAL AND CRYSTAL, A CENTRAL SPINDLE CARRYING SAID HAND AND EXTENDING REARWARDLY THROUGH SAID DIAL AND PLATE AND INTO THE INTERIOR OF SAID CASING, DRIVING MEANS IN SAID CASING COUPLING WITH SAID SPINDLE TO DRIVE IT, A TIME-INDICATING HAND BETWEEN SAID DIAL AND CRYSTAL, A SHAFT COAXIAL WITH SAID SPINDLE AND CARRYING SAID TIMEINDICATING HAND, A SELF-CONTAINED CLOCKWORK UNIT DISPOSED IN SAID CASING ON THE REAR OF SAID PLATE WHOLLY AT ONE SIDE OF SAID SPINDLE, MEANS REMOVABLY SECURING SAID CLOCKWORK UNIT TO THE REAR OF SAID PLATE FOR EASY REMOVAL AS A COMPLETE UNIT, SAID CLOCKWORK UNIT HAVING A ROTARY OUTPUT MEMBER ALIGNED WITH AN OPENING IN SAID PLATE, MEANS INCLUDING GEAR MEANS BETWEEN SAID DIAL AND PLATE DRIVINGLY CONNECTING SAID SHAFT OF SAID TIME-INDICATING HAND WITH SAID OUTPUT MEMBER OF SAID CLOCKWORK UNIT TO BE DRIVEN THEREBY, A CHART-HOLDING MEMBER ROTATABLY MOUNTED COAXIAL WITH SAID SPINDLE AND HAVING A CHART-SUPPORTING SURFACE IN A PLANE IMMEDIATELY BACK OF SAID CLOCKWORK UNIT, MEANS INCLUDING SAID GEAR MEANS DRIVINGLY CONNECTING SAID CHART-CARRYING MEMBER WITH SAID OUTPUT MEMBER OF SAID CLOCKWORK UNIT AND SAID TIME-INDICATING HAND SHAFT, AND A STYLUS IN SAID CASING IN POSITION FOR ENGAGEMENT WITH A CHART ON SAID CHART-HOLDING MEMBER, SAID COVER BEING SWINGABLE BY SAID PIVOTAL MOUNTING TO AN OPEN POSITION AFFORDING ACCESS TO SAID COMPLETE REMOVABLE CLOCKWORK UNIT. 